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02-18-2010, 02:23 AM   #226
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QuoteOriginally posted by Frink Quote
I wonder if the new selection of lenses will be backwards compatible with the film 645's, or if we'll have a repeat of the FA vs DA / DX vs FX development.
I think they won't - I think images of the prototype DFA645 55mm/2.8 showed that it was without aperture ring.

Another question which suddenly occured to me: What if they make the new 645 lenses in such a way that they can provide a fully automatic (SDM + aperture) adapter for use with K-7 and other SDM-capable DSLRS? Wouldn't that be cool?

Different question: Anyone have any guess to what happened to the "Mirror up" button? Hopefully just moved... and btw what is that other knob on the right side of the mirror housing? And: Doesn't the fact that there's no mirror up button mean that the manual leak was a fake?

(On the other hand, who knows if they just photoshopped away the button and that it will re-emerge when they shed a little more light on the 645 in a few days :-))

02-18-2010, 02:39 AM   #227
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The the 645s all had A modes on the focusing ring. So, you can probably use the digital lenses on the film cams...if they cover the full frame.
02-18-2010, 03:45 AM   #228
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QuoteOriginally posted by lithos Quote
The the 645s all had A modes on the focusing ring. So, you can probably use the digital lenses on the film cams...if they cover the full frame.
I would be surprised if they decide to use a reduced image circle - since they may use larger sensors later.
02-18-2010, 08:55 AM   #229
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QuoteOriginally posted by gazonk Quote
... and btw what is that other knob on the right side of the mirror housing?
I think thats the PC sync cover

02-18-2010, 05:18 PM   #230
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50 MP in real life

Many have questioned that a camera capable of 30, 40, or 50 MP is a desirable thing to have.

Therefore, I post a sample photo which has been made publicly available by photographer Petter Hegre.

The original image contains nudity but can be shown to kids in all western countries w/o limitation. Nevertheless, I censored the attached 10% sample image because I know that Adam is more restrictive in this regard.

Shot with a H3DII-50 in November 2009.

Link to original photo: http://cdn.hegre-art.com/img/Hegre-art_sample.zip

Attached image with only 1/100 of original pixels (by Petter Hegre):

Last edited by falconeye; 06-15-2011 at 05:29 AM.
02-18-2010, 06:21 PM   #231
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But you are probably limited to Program mode and shutter-priority mode only, like how DA lenses work on a ZX-5n(which has very similar congtrol layout as the 645N)

QuoteOriginally posted by lithos Quote
The the 645s all had A modes on the focusing ring. So, you can probably use the digital lenses on the film cams...if they cover the full frame.
02-18-2010, 10:29 PM   #232
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QuoteOriginally posted by gazonk Quote
I would be surprised if they decide to use a reduced image circle - since they may use larger sensors later.
Yeah. The reduced image circle was done on the APS-C cams to reduce the size of the lenses. I don't see size reduction to be all that important with an MF camera...especially since the 645N wasn't that much bigger than a Nikon F5.
02-19-2010, 12:55 AM   #233
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QuoteOriginally posted by lithos Quote
Yeah. The reduced image circle was done on the APS-C cams to reduce the size of the lenses.
actually, it was done the other way around - lenses are made smaller because of the smaller sensor. smaller sensor = much smaller cost of the sensor.

02-19-2010, 02:21 AM   #234
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QuoteOriginally posted by elkarrde Quote
actually, it was done the other way around - lenses are made smaller because of the smaller sensor. smaller sensor = much smaller cost of the sensor.
Actually, I think you two agree

Smaller sensor -> possible to use smaller image circle -> possible to make smaller lenses
02-19-2010, 03:17 AM   #235
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QuoteOriginally posted by gazonk Quote
Actually, I think you two agree
Things aren't as simple as they appear to be.

Obviously, a smaller sensor allows for a smaller image circle. And a smaller focal length at same field of view.

And at the same f-stop, the smaller focal length allows for a smaller lens diameter, actually proportionally shrunk to the image circle.

The smaller image circle only helps decreasing a lens' size if it is larger than the lens diameter in the first place. Which is the case only for short to slow medium focal lenses. I.e., fast medium and long focal lenses don't benefit from a smaller image circle.

It is even more complicated: the smaller image circle requires smaller f-stops for similiar performance requiring higher refraction and more and thicker lens elements for a similiar performance in LW/PH. Therefore, for a given image quality, the smaller image circle can require the larger lens.
02-19-2010, 03:20 AM   #236
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New DFA645 lenses will be lenses for standart image circle. Like FA645.
D=optimized for digital sensor.
02-19-2010, 06:13 AM   #237
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QuoteOriginally posted by falconeye Quote
Many have questioned that a camera capable of 30, 40, or 50 MP is a desirable thing to have.

Therefore, I post a sample photo which has been made publicly available by photographer Petter Hegre.

The original image contains nudity but can be shown to kids in all western countries w/o limitation. Nevertheless, I censored the attached 10% sample image because I know that Adam is more restrictive in this regard.

Shot with a H3DII-50 in November 2009.

Link to original photo: http://cdn.hegre-art.com/img/Hegre-art_sample.zip

Attached image with only 1/100 of original pixels (by Petter Hegre):
Indeed. There is definitely A LOT of details here!!
02-19-2010, 07:02 AM   #238
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QuoteOriginally posted by cousinsane Quote
But you are probably limited to Program mode and shutter-priority mode only, like how DA lenses work on a ZX-5n(which has very similar congtrol layout as the 645N)
Not so simple, I'm not sure the 645 bayonet is compatible with K bayonet (other than mechanical). Adapters do exist. There were never any adapter for 5645 to K maintaining any electrical/AF capabilities.

Why would it come now ?
02-19-2010, 07:14 AM   #239
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I wonder how it will do with the already established Mamiya line up?
02-19-2010, 07:21 AM   #240
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QuoteOriginally posted by ogl Quote
New DFA645 lenses will be lenses for standart image circle. Like FA645.
D=optimized for digital sensor.
This is your opinion.

You have a track record to post opinions as facts. Maybe, think about it. If in doubt, prepend your post by an innocent "IMHO". Thanks.
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